When a workpiece such as an electronic part is mounted on a substrate, a machining device used to pass the workpiece against the substrate is used. In this machining device, a linear motor or the like is used as means used to pass the workpiece (Patent Literature 1).
In this machining device, it is necessary to press the workpiece at a fixed load (pressure) or more so as to securely mount the workpiece on the substrate. At this time, in order to prevent damage of the workpiece or the substrate, it is necessary for the load to be as light as possible. In the machining device, it is necessary to control the workpiece load with high accuracy.